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Author  Topic

USA
635 Posts

 Posted - 06/19/2012 :  21:45:18 What result do you get? I get 13, but my son insists it is 4.16-6x22(5-3)Thanks,Gisele

royhaas
Moderator

USA
3059 Posts

 Posted - 06/20/2012 :  09:50:03 16-622(5-3)=16-622(2)=16-624=16-124=16-3=13.

USA
635 Posts

 Posted - 06/20/2012 :  10:17:05 quote:Originally posted by royhaas16-622(5-3)=16-622(2)=16-624=16-124=16-3=13.Thanks Roy. My thoughts exactly. This question will be included in an upcoming Flash game.

Ultraglide

299 Posts

 Posted - 06/25/2012 :  12:40:35 Looking at part of the question, i.e. 6x22(2), this is the same as 6x22x2. Now if we follow the order of operations - multiplication and division in order from left to right this gives 12. So the final answer is 4.

USA
635 Posts

 Posted - 06/25/2012 :  15:53:14 quote:Originally posted by UltraglideLooking at part of the question, i.e. 6x22(2), this is the same as 6x22x2. Now if we follow the order of operations - multiplication and division in order from left to right this gives 12. So the final answer is 4.Thank you for your input, UltraGlide. I guess if us math folk can't agree on the solution, then this is not a good problem to hard code into a Flash game. I will post it on Facebook, though.Gisele

Ultraglide

299 Posts

 Posted - 06/25/2012 :  17:02:22 If you want to answer to come out to 13, just put parentheses around the 2(2) i.e. [2(2)].

the_hill1962

USA
1469 Posts

 Posted - 06/26/2012 :  15:54:23 I agree that the answer is 4.This is the reason why I have never liked the"Please Excuse My Dear Aunt Sally" (or PEMDAS) acronym.They do come to me knowing the acronym PEMDAS though so I suppose it served its purpose (having them remember the order).I tell them since multiplication and division are at the same level, so that PEMDAS is misleading if you forget that detail.This topic provides an example.I write on the board PEmdAS.I hook together the md and the AS (sort like they do in company logos hooking together letters). Edited by - the_hill1962 on 09/13/2012 12:47:48

royhaas
Moderator

USA
3059 Posts

 Posted - 06/27/2012 :  11:32:08 If you faithfully follow the PEMDAS precedence rules, then the answer on almost any calculator is 4,16-6*2/2*(5-3)=16-6*2/2*2=16-6*2/2*2=16-(6*2/2*2)=16-12=4. Multiplication and division have the same precedence, so the (re-)grouping is allowed. It seems that this is a common problem when both multiplication and division are concerned. That's why I trust my calculator more than my hand arithmetic.

USA
635 Posts

 Posted - 06/27/2012 :  11:38:58 Thanks everyone for your input!Gisele
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